CGAL::Gmpq

Definition

An object of the class Gmpq is an arbitrary precision rational number based on the Gnu Multiple Precision Arithmetic Library.

#include <CGAL/Gmpq.h>

Is Model for the Concepts

Field
RealEmbeddable
Fraction

Creation

Gmpq q;
creates an uninitialized Gmpq q.

Gmpq q ( int i);
creates a Gmpq initialized with i.

Gmpq q ( Gmpz n);
creates a Gmpq initialized with n.

Gmpq q ( Gmpfr f);
creates a Gmpq initialized with f.

Gmpq q ( int n, int d);
creates a Gmpq initialized with n/d.

Gmpq q ( signed long n, unsigned long d);
creates a Gmpq initialized with n/d.

Gmpq q ( unsigned long n, unsigned long d);
creates a Gmpq initialized with n/d.

Gmpq q ( Gmpz n, Gmpz d);
creates a Gmpq initialized with n/d.

Gmpq q ( double d);
creates a Gmpq initialized with d.


Gmpq q ( std::string str);
creates a Gmpq initialized with str, which can be an integer like "41" or a fraction like "41/152". White space is allowed in the string, and ignored.

Gmpq q ( std::string str, int base);
creates a Gmpq initialized with str in base base, which is an integer between 2 and 62. White space in the string is ignored.

Operations

std::ostream& std::ostream& out << q writes q to the ostream out, in the form n/d.

std::istream& std::istream& in >> & q reads a number from in, then converts it to a Gmpq. The number may be an integer, a rational number in the form n/d, or a floating-point number.

There are two access functions, namely to the numerator and the denominator of a rational. Note that these values are not uniquely defined. It is guaranteed that q.numerator() and q.denominator() return values nt_num and nt_den such that q = nt_num/nt_den, only if q.numerator() and q.denominator() are called consecutively wrt. q, i.e. q is not involved in any other operation between these calls.

Gmpz q.numerator () returns the numerator of q.
Gmpz q.denominator () returns the denominator of q.

Implementation

Gmpqs are reference counted.